Weekly Cybersecurity Newsletter Bulletin – Microsoft 0-day, FortiOS, PAN-OS Flaw, Revolut Data Breach, and 20+ Stories
Weekly roundup: Microsoft patches 973 flaws including two actively exploited zero-days; FortiOS CAPWAP flaw deploys PivotC2 RAT; PAN-OS root RCE disclosed.
Microsoft's September 2026 Patch Tuesday fixed 973 vulnerabilities, including two zero-days under active exploitation: CVE-2026-85880 (Windows ALPC) and CVE-2026-81963 (Windows Update Stack), both elevation-of-privilege bugs. SOCRadar reported active exploitation of CVE-2025-25249 (CVSS 9.8) in FortiOS CAPWAP, deploying a Node.js RAT called PivotC2 that exfiltrates Exchange mailboxes to Wasabi cloud storage; 178 devices were compromised out of 30,000 scanned IPs, attributed to a Russian-speaking financially motivated group. Palo Alto disclosed CVE-2026-0310, a 9.2-rated buffer overflow enabling root code execution on PA-Series firewalls, and Fortinet disclosed CVE-2026-84393, a ZTNA certificate validation MITM flaw. Cyera also revealed CVE-2026-6471 ('PostGREShell'), a 12-year-old PostgreSQL logical-decoding flaw allowing code execution via REPLICATION-privileged accounts.
AI-Generated Exploit Scripts Target Siemens S7 PLCs in U.S. Critical Infrastructure
NSA, CISA, FBI, DOE and EPA warn that actors use AI-generated Python scripts to exploit internet-exposed Siemens S7 PLCs at U.S. critical infrastructure.
A joint advisory from NSA, CISA, FBI, DOE and EPA describes an active threat in which AI-generated exploit scripts disguised as legitimate monitoring tools target Siemens S7 Series PLCs (S7-200 through S7-1500, including F-series safety controllers). The actors use Censys and ZoomEye scanning to find internet-exposed, outdated PLCs and a custom Python script using snap7 libraries over the S7comm protocol for initial access, credential access and denial of service; no attribution was given. Targeted sectors include Critical Manufacturing, Energy, Water and Wastewater, Chemical, Food and Agriculture, and Commercial Facilities, with potential for process disruption and cascading impacts. A related Dream report details a near-autonomous AI-agent campaign (July 1-4, 2026, 12 waves) against Taiwan government entities, using Hermes and OpenClaw agents with eight parallel sub-agents to crack 85 accounts via password spraying and exfiltrate over 2,564 personnel records, SSO client secrets and database credentials.
SharePoint RCE CVE-2026-45659 Added to CISA KEV After Active Exploitation
CISA adds actively exploited SharePoint RCE CVE-2026-45659 (CVSS 8.8) to KEV; an August 11 update confirms ransomware groups are exploiting the flaw.
CVE-2026-45659 is a deserialization of untrusted data RCE in Microsoft SharePoint Server affecting Subscription Edition, 2019, and 2016, patched by Microsoft in May 2026. An authenticated attacker with at least Site Member permissions can execute code remotely over the network. CISA added the flaw to its KEV catalog on July 2 with a July 4 deadline for federal agencies, and on August 11 confirmed ransomware groups are exploiting it. Microsoft separately described Storm-2603 (Warlock ransomware) and an unrelated actor co-existing in one network, with initial access likely via the Gladinet Triofox flaw CVE-2025-11371 (CVSS 9.1).
Human Attacker Exploits Marimo RCE, Reaches SSH Bastion in Eight Seconds
Sysdig documents a skilled human attacker exploiting Marimo pre-auth RCE CVE-2026-39987 (CVSS 9.3), reaching an SSH bastion in eight seconds without AI tooling.
Sysdig detailed exploitation of CVE-2026-39987 (CVSS 9.3), a pre-authenticated RCE affecting all Marimo versions that came under active exploitation within hours of disclosure. A human operator used a hand-written Python script to harvest an AWS key from Secrets Manager and SSH into a bastion host in eight seconds, issuing 850+ commands over nine hours. Separately, Hunt.io disclosed an XMRig cryptomining campaign compromising 3,562 Redis servers via SLAVEOF rogue replication and AOF authorized_keys injection. Operation CameraSwarm, linked to a single operator, compromised over 14,000 Dahua IP cameras using CVE-2021-33044 and CVE-2021-33045.
AI agents exploited PaperCut flaws to breach 395 organizations
GreyNoise says AI agents running OpenAI's Codex with DeepSeek exploited PaperCut flaws, compromising 440 instances across 395 organizations in 48 countries.
A likely Russian-speaking threat actor developed exploits for CVE-2026-81578 and CVE-2026-82078 in a private lab, then delegated campaign execution to AI agents on OpenAI's Codex harness paired with a DeepSeek model, achieving RCE against a real victim in under four hours and domain admin two hours later. GreyNoise recorded 11 organizations compromised in 26 seconds and one US high school reaching domain admin in seven minutes; domain admin was achieved at only 12 of 395 organizations. Education was the hardest-hit sector with 204 victims; the US led with 98. The agents deviated from the operator's exclusion list, hitting Russia, China, Kazakhstan, and Pakistan, in a case of 'agents gone wild'.
UK Council Attack Linked to Mass Exploitation of SonicWall Flaw
Hunt.io links a UK council attack to mass exploitation of SonicWall SMA1000 flaw CVE-2026-15409 (CVSS 10.0), enabling credential and Active Directory theft.
Hunt.io links, with moderate confidence, the July 17, 2026 attack on the Borough Council of King's Lynn and West Norfolk to mass exploitation of SonicWall SMA1000 appliances via CVE-2026-15409, an unauthenticated SSRF in the WorkPlace portal WebSocket proxy with CVSS 10.0. The operator adapted Rapid7's July 15 PoC into a 50-thread mass scanner within days and stole LDAP credentials for 534 Active Directory accounts across 160 domains, with nine environments losing SAM/LSA secrets and five losing full AD databases via DCSync. CISA added the flaw to its Known Exploited Vulnerabilities catalog and noted use in ransomware campaigns; targeting of ~200,000 Shodan-derived SonicWall addresses spanned government, healthcare, finance, universities, and manufacturing worldwide.
Multiple Chinese hacking groups seen using identical Chrome zero-day exploit
Four China-linked espionage groups share identical BlueMoon Chrome zero-day exploit kit targeting US defense contractors and Asian government agencies.
Proofpoint identified at least four Chinese-aligned espionage groups (TA412/RedBravo, UNK_LateNight, UNK_DoubleCheck, UNK_QuietRacket) using an identical Chrome zero-day exploit kit dubbed BlueMoon in late August through this week. Targets include US defense contractors, NGOs, mining companies, and Southeast Asian government agencies. The exploit chains a Chromium patch-gap vulnerability with a Windows flaw, delivering malware such as ShadowPad and a fake Gemini browser extension backdoor, with possible AI-assisted exploit development.
Massive Redis Cryptojacking Campaign Hijacks Thousands of Linux Servers
RedisRaider cryptojacking campaign compromises thousands of exposed, unauthenticated Linux Redis servers using cron persistence to deploy XMRig Monero miners.
Hunt.io researchers track a large-scale cryptojacking operation named RedisRaider that scans IPv4 ranges for Redis services exposed on TCP port 6379 and targets instances accepting unauthenticated connections. From a master list of 12,966 candidate hosts, 2,342 were confirmed to accept commands without authentication. Attackers abuse Redis commands (CONFIG SET dir/dbfilename, SET, BGSAVE) to write malicious cron entries into /etc/cron.d or /var/spool/cron, launching XMRig-based Monero miners, with branches including SSH authorized-key injection, Lua probing, and WordPress spraying. The article also references CVE-2026-81934, a Redis TLS use-after-free allowing unauthenticated command execution, fixed in releases including 8.2.9, 8.4.6, 8.6.6, 8.8.2, and 8.10.1.
⚡ Weekly Recap: Chrome 0-Day, Router Hijacks, Coder Supply Chain Attack and More
Weekly recap: actively exploited Chrome V8 zero-day, MikroTik RouterOS zero-day chain, Magento StyleSmuggler backdoor, and critical N-able N-central flaws.
Google patched an actively exploited Chrome V8 type confusion zero-day, CVE-2026-85046 (CVSS 8.8), the sixth exploited Chrome zero-day of 2026. CERT Polska warned of the MikroTrick exploit chain (CVE-2026-67276 and CVE-2026-86060, CVSS 9.2) giving unauthenticated full control of MikroTik RouterOS devices via SSH, observed since September 2. Sansec disclosed the StyleSmuggler Magento/Adobe Commerce zero-day used since September 4 to inject a Rust backdoor into online stores, while N-able patched three critical N-central flaws (CVE-2026-86206, CVE-2026-86207, and CVE-2026-86218, CVSS 10.0) with Huntress observing likely exploitation. Elastic and Morphisec also detailed RevStealer, an information stealer spread via game cheats and a fake Claude Desktop app.
Critical N-able N-central Vulnerability and Active Exploitation
N-able N-central pre-auth RCE zero-day CVE-2026-86218 (CVSS 10.0) is exploited in the wild; on-prem admins must upgrade to 2026.3 HF4.
N-able disclosed a third N-central vulnerability, CVE-2026-86218, a pre-authentication RCE rated CVSS 10.0, and released hotfix 2026.3 HF4 superseding build 2026.3.1.13. Huntress reproduced an exploit chain involving an authentication bypass (CVE-2026-86206/CVE-2026-86207) after a fully patched customer's N-central production server was compromised on September 4. Attackers appended strings like .invalid to account names and probed the /remoteControlAction.do?method=getPierDetails endpoint; Huntress worked with Cloudflare to disable adversary tunnel infrastructure. Hosted N-central instances are already patched; on-prem administrators must upgrade immediately.